Photolitho machine



Feb. 10, 1925.

H. C. BOEDICKER rao'rbm'rno MACHINE Filegi July l, 1922 s Sheets-Sheet 1INVENTOR A TTORNE YJ Feb. 10, 1925.

PHOTOLITHO MACHINE Filedjuly l, 1922 5 Sheets-Sheet 2 7w 76 7 177 I 7f 7INVENTOR.

XL TZ BY A TTORNEYJ H. C. BOEDICKER PHOTOLITHO MACHINE 5 Sheets-Sheet 5Filed July 1, 1922 A TTORNEYV H. C. BOEDICKER PHOI'OLITHO MACHINE FiledJuly 1, 1922 5 Sheets-Sheet 4 IN VEN TOR c" 7 W A TTORNEYJ H. C.BOEDICKER PHO'I'OLITHO MACHINE Filed July 1, 1922 5 Sheets-Sheet 5 i EEEQEFW IN V EN TOR.

A TTORNE YJ' Patented Feb. 10, 1925.

, UNITED STATES HERMAN G. BOEDIGKER, OF NEW YORK, N. Y.

:rHo'roLrrHo MACHINE.

Application filed July 1,

To all whom it may concern:

Be it known that I, HERMAN O. BOEDICK- ER, a citizen of the UnitedStates, residing at New York city, in the county of New York and Stateof New York, have invented certain new and useful Improvements inPhotolitho Machines, of which the following is a full, clear, and exactdescription.

This invention relates to methods and apparatus for producing multiplephotographic plates for color, register work in the art of makingphotolithographic, typographical or rotogravure printing plates orcylinders. In the preparation of printing plates for color printing, amaster color negative of the picture to be printed is prepared for eachcolor to be printed, and these negatives are then photographed uponsensitized printing plates, which when developed are used for printingthe colors successively upon a paper or article. Where a quantity ofprints are to be made it has been a common practice to make a pluralityof prints of each color negative upon each platewith the negativesspaced correspondingly upon all the plates so that when one is properlyplaced in the printing press for correct printing of one color, all of.the other prints on the same plate will be in proper printing position.If the prints upon one color plate are not spaced exactly in accordancewith the spacing in another color plate of the same set of prints, theplates must be discarded and remade, because the color prints nadetherefrom will never register. In making the multiple prints upon eachcolor plate, errors of spacing are likely to occur, owing to the failureof the operator to read and set the indicators or scales correctly inthe spacing of the cameras for each exposure.

An object of this invention is to provide an improved and simple methodand apparatus for preparing plates for use in multiple print colorregister work, in accordance with which any variation in spacing of theprints upon the lates will be immaterial; with which aoso ute registerof the prints in color work can always be obtained with certainty andwith which any desired number of duplicates on one plate for each colormay be obtained by the step and repeat method with absolute register ofthe color plates in printing. A further object is to provide an improvedapparatus for these purposes which is eiiicient, durable, andinexpensive. Other objects and advantages will be ap- 1922.. Serial No.572,177.

parent from the following description of an embodiment of the invention,and the novel features will be particularly pointed out in claims.

In the accompanying drawing:

Fig. l is a side elevation of a machine constructed in accordance withthe invention and arranged for fprojection printing;

' Fig. 2 is a plan 0 the same when arranged for contact printing;

Fig. 3 is a transverse sectional elevation through the same whenarranged for contact printing;

Fig. 4 is a sectional plan of the same;

Fig. 5 is a fragmentary sectional plan of the mechanism for propellingthe camera supporting carriage toward and from the plate supportingframe;

v Fig. 6 is a transverse section through a portionof the same forshowing the clutch coupling between the worm carried by the carriage andthe frame; I

Fig. 7 is a sectional plan through the same parts;

Fig. 8 is a diagram of the color plates showing the method of spacingthe prints thereon;

Fig. 9 is a diagram illustrating the prinei le of color printing, and

ig. 10 is a sectional elevation through one of the plate holders.

The main support or base for the apparatus comprises a horizontallydisposed latform 1 which is preferably supporte at numerous points byhelical springs 2 Which serve to absorb vibrations that might otherwisebe transmitted to the platform, and thence to the other parts of theapparatus. At one end of the platform a vertically extending frame 3 isprovided for supporting the printing plates or negative holder boxes.The frame 3 is braced in a suitable manner such as by arcuate bracesprovided at suitable intervals along the width of the platform. Theplatform is provided upon its upper face, along each side thereof, withVshaped rails 5 and 6 which support and guide the main carriage 7 formovement along the platform toward and from the end. frame 3. The maincarriage is provided with spool-like rollers 8 which ride upon the rails5 and 6 and guide the carriage along the platform.

The platform 1 adjacent the rail 6, is pro vided with a rack 9 (Figs. 3and 5) with which meshes a pinion 10 that is slidably but non-rotativelycarried by the shaft 11. The shaft 11. is rotatably carried by the mamcarriage 7 and extends transversely of the the rack 9. The pinion 10 isprovided with a boss-like axial extension 13 upon its inner face, andthe extension has in its periphery an annular groove 14'that is engagedby pins 15 upon the ends of a fork 16. The fork 1 6 is plvotally carriedby the carriage, and is provided with an angular extension 17, forming ahandle by means of which the fork may be oscillated about its pivot toshift the pinion axially along the shaft 11 into and out of engagementwith the rack 9. The shaft 11 at its inner end is provided with a bevelgear. 18 which meshes with a bevel gear 19, carried by a shaft 20. Theshaft 20 is rotatably carried by the carriage 7 and extends transverselyof the shaft 11.

The shaft'20 is provided with a pinion 21 which meshes w1th an idler 22,rotatively carried by the carriage and in turn meshing with a pinion 23carried by a shaft 24. The shaft 24 is rotatively carried by thecarriage 7 so as to extend endwise thereof, that is, in the direction oftravel of the carriage? upon the platform, and is provided with screwthreads 25 by means of which the carriage may be shifted along theplatform at a very slow rate in a manner to-be described. The platformis provided with an inverted casing 26 through the ends of which theshaft-24 freely passes. \Vithin this casing 26, half nuts 27 and 28 aremounted for sliding movement toward and from the threaded portion 25 ofthe shaft 24, and are providedu on their abutting concave faces withthrea with the threads 25 of the shaft and act together as a single nut.To maintain the sections 27 and 28 in proper meshing relation withrespect to the threads, one of the sections is provided with dowel pins29 which. slidingly engage in-recesses in theabutting face of the othersection, and permit of a limited approach and separation of the sectionswith respect to one another. The sections are each provided with arecess 30 through which shafts 31 and 32 extend. These shafts3l and 32are rotatively carried by'tne casing in positions parallel with theshaft 24 and each is provided with an eccentric cam 33 which is disposedin a recess 30 and engageswith opposite walls thereof so that when theshafts 31 and 32 are rotated, the eccentric cams will shift the sections27 and 28 toward and from the shaft The shaft 31 is provided exteriorlyofthe s which are adapted to engagecasing 26 with a crank arm 34 which.at its free end is connectedthrough a link 35 w1th a second crank arm'36provided upon the.

outer end of the shaft 32. This insures concomitant rotation together ofthe shafts 31 and 32. A link 37 is pivotally connected to the crank arm34 and extends through a side faceof the platform where it is pivotallyconnected to an operating lever 38. The operation of the lever 38 causesa concomitant operation of the shafts 31 and32 and thereby concomitantoperation of the eccentric cams 33 which shift the split nut sec-" tions27 and 28 into and'out of engagement with. the threaded-portion 25 ofthe shaft 24. If, when the lever 38 has been operated to couple thesplit nut sections 27 and 28 to the shaft 24, the shaft 24 is rotatedthrough the hand wheel 12, shaft 11, gears 18 and 19, shaft 20, pinions21, 22- and 23, the shaft 24 will, by its threaded engagement with thenut sections 27 and 28, be shifted endwise of the casing 26 and 'theplatform 1 upon which it is carried. A very slow movement is thusimparted to the main carriage 7 for propelling it lengthwise of theplatform. Owing to the reduction gearing effect provided by the threadedshaft 24 and the nut sections 27 and 28, a minimum of power ap-.

plied to the hand wheel 12 will be effective.

in causing movement of themain carriage along the platform and greatpower would be necessary to move the carriage except by rotation of theshaft 24. During this movement' by the shaft 24, it is, of course,understood that the pinion 10 is disconnected from the rack 9 of theplatform. If now the nut sections are shifted out of engagement with thethreaded shaft 24, by operation of the lever 38, the carriage is freeand may berolled along the platform manually, or the lever arm 17 may beshifted to operate the fork 16 and shift the pinion 10 into mesh withthe teeth of the rack 9 upon the platform. If then the hand wheel 12 isoperated the pinion 10 which is rotated thereby, will,

by its engagement with the rack 9 propel tne carriage at a comparativelyrapid rate along the platform.

The end frame 3 is provided at each side with vertically extendingthreaded shafts 39 and 40 which arepivoted for rotation therein in asuitable manner. The shafts 39 and 40 are provided adjacent their lowerends with worm wheels 41 (Fig. 4) which mesh with worms 42 provided upona horizontally and transversely extending shaft 43. The shaft 43 isprovided at its outer end with a hand wheel 44 (Fig. 1) by means ofwhich the shaft maybe rotated. The shafts 39 and 40 have threadedengagement with the opposite ends of the contact or plate carrylng frame45 (Fig. 3) which is mounted for vertical sliding movement .in the frame3.

ran

The frame is provided at its ends and intermediate of its ends withspaced vertical guide posts 46 (Figs. 1 and 3) having upon their edgesfacing one another, grooves 47 which receive and guide the ends 4.8 ofstretcher bars 9. The contact or plate carrying frame i5 is provided inthe space between each pair of guides 46 with vertically disposedthreaded shafts 50 (Figs. 3, a and 10) which are fixedly carried in theupper and lower portions of the contact frame. A beveled gear 51 isprovided upon each shaft 50 and has threaded engagementtherewith so thatwhen the beveled gear is rotated it will be shifted axially along thethreaded shaft 50. Each beveled gear 51 is rotatably carried by theadjacent stretcher bar i9 so that when the beveled gears are rotated thestretcher bar will be shifted vertically, being guided in its verticalmovement by the enlarged ends 48 of the bar 49 which slide in thevertical guide grooves 17.

Each stretcher bar 49 is provided with a rotatable shaft 52 (Figs. 3 and10) extending parallel therewith and provided upon its ends with beveledgears 53 which mesh with the beveled gears 51. The shaft 52 is providedat an intermediate point with a beveled gear 54 which meshes with abeveled gear 55 rotatably carried by the stretchor bar l9. A crank arm56 is connected to the beveled gear 55 for rotating the same which, byits operation, rotates the shaft 52 and thereby rotates the bevel gears51. This operation raises or lowersthe stretcher bar 001 trolledthereby.

hor contact printing, the lower edge of the contact frame is providedwith suitable clamps 57 (Fig. 10) for receiving and holding the loweredges of a plurality of sensitized plates 58 which when developed are toform the plates for printing the various colors upon the article orpaper. Each stretcher bar i9 is provided upon a forwardly inclined face59 with a plurality of clamps 60 which receive and hold the up er edgesof the sensitized plates 58. If, arter a plate has been clamped at itsupper and lower edges, the crank arm 57, upon the stretcher bar 49 towhich it is connected, is rotated, the stretcher bar will be shifted tostretch the plate and hold it taut during the printing operation. A

To receive and counteract the pressure upon the plate during the contactprinting operation, a pressure beam 61 (Figs. 3, 4'

and 10) is provided which extends the full width of the end frame and atits ends slides in grooves (52 (Fig. 4) in the end frame. A. shaft 63(Figs. 1 and 4) is rotatably carried by the end frame and extendstransversely across the platform. Adjacent its ends, the shaft 63 is.rovided with worm gears (Fig. at) which mesh with corresponding wormgears (not shown) upon shafts 65, which are rotatably carried by the endframe and at their upper ends have threaded engagement with the endportions of the pressure beam 61. When the shaft 63 is rotated thethreaded shafts 65 will be rotated, and the latter, by their threadedengagement with the pressure beam, will shift the pressure beam in onedirection or the other vertically so as to position the beam atdifferent heights. The shaft 63 at the end projecting from one of theside faces of the platform is provided with an operating hand wheel 66(Fig. 1) to facilitate its rotation. The face of the pressure beam 61against which the sensitized plates abut is preferably provided with arubber or other suitable somewhat resilient material 60.

The main carriage is provided upon its upper face with a dovetailedguide groove 67 (Fig. 1) extending transversely of the platform 1 andalong the edge of the carriage adjacent the end frame. A plurality ofauxiliary or camera carriages 68 are provided, each with an undercut rib69 upon its lower face and adjacent one end which fits in and slides inthe dovetailed guide groove 67 so as to guide the auxiliary carriagestransvers ly of the platform 1, that is, from side to side upon the maincarriage 7. The auxiliary carriages at their other ends have each asimple sliding contact with the main carriage.

A shaft 70 is rotatably carried by the main carriage 7 so as to extendfrom side to side, adjacent to the dove-tailed guide groove 67 andadjacent the u per edge of the carriage. This shaft 70 has threadedengagement with each of the auxiliary carriages so that when the shaftis rotated the auxiliary carriages will be shifted from side to sideupon the main carriage concomitantly and equally. A similar and parallelshaft 71 is rotatably carried by the main carriage adjacentto the otherbearing surfaces between thecarriages and likewise has threadedengagement with each of the auxiliary carriages.

The shafts 70 and 71 at corresponding ends are provided with beveledgears 72 and 73, respectively, which mesh with beveled gears 74 and 75,respectively, carried upon the opposite ends of a shaft 76 which isrotatably carried by the main carriage. The shafts 70 and 71, will,therefore, be geared for rotation together and operation of either ofthese shafts will cause a. corresponding and equal operation of theother shaft so that the auxiliary carriages will be shifted,

equal amounts at each end concomitantly,

which prevents binding in the dovrtailed guide groove 67 One cf theshafts, such as 70 is provided at an end with an operating hand wheel 77by which the-shifting of the auxiliary carriages may be accomplished.

.' Suitable indicating ineans may be provided for indicating the amountof movement of the aux liary carriages. For example, a micrometer dial78 may be provided upon the shaft 70 immediately to the rear of theoperating hand wheel 7 7 for rotation with the shaft, and the scalethereon is adapted to cooperate with a stationary indicating pointer 79carried by the main carriage. A suitable counter not shown) may becarried by the main carriage 7 in position to be tripped by a lug uponthe micrometer dial at each ro ation thereof, for countingand indicatingthe number of rotations of the shaft 70 at eaclrspacing movement of theauxiliai v'c'arriagcs.

An electric motor 80 may be mounted upon the main carriage 7 and gearedthrough reduction gears 81, 82. 83, idler 84; to a pinion 85 carriedupon the shaft 70. Operation of the motor, therefore, serves to-rotatethe shaft 70 and relieve the operator of the burden of manually rotatingthe shafts 70 and 71. The motor is preferably used for accomplishing themajor portion of the shifting movements of the auxiliary carriages,the'finishing portion of each of the movements being accon plished bymanual operation of the hand wheel 74 to insure accuracy; I 1

Suitable camera or other photographic printing mechanism is providedupon each auxiliary carriage. For'this purpose each auxiliary carriageis provided in its upper face with an undercut guide groove 86 (Fig. 3)in which a plate 87 is slidin'gly disposed and confined. The guidegrooves 86 extend from endto end of the auxiliary carriages and in adirection transversely of the guiding groove 67- of the main carriage sothat the plates 87 will, in moving along the guide grooves 86, approachor recede from the end frame 3. Upon the upper face of each plate 87, Iprovide a lamp casing 88 (Figs. 1, 2-

and and a collecting hood 89 which opens into the lamp casing. Withinthe lamp casing, I providea suitable and powerful source of illuminationsuch as an arc lamp, for supplying the light necessary for the printing"operation.

in contact printin a negative box .90 is supported by the hood 89 withprovision for angular adjustment relatively thereto. The negative andnegative glass are secured in the end of the negative box facing the endframe in a suitable manner srch as is disclosed, for example, in my U.S. Patent #1327752, so that each negative and its negative box may 7 bebrought into direct contact, with its corresponding sensitized plate 60and held firmly incontact therewith during the printing operation.

The light from the lamp casing 88 passes through the collecting hood 89,through the negative box 90 and the negative, which serves to photographeach negative directly upon the sensitized plate with which it is incontact. The angular adjustment of the negative box enables angularadjustment of the negatives into corresponding POSlLlOIlS upon theirsupportsso that corresponding-i e the colors yellow, red, blue andblack.

A shaft 91 is rotatably mounted in a bearing 92 upon the main carriage 7and extends in a direction transversely of the platform. The shaft 91passes through and has a slidable and rotatable bearing in the auxiliarycarriage 68 upon which the camera A ismounted. An eccentric cam 93 iskeyed to the shaft 91 for rotation therewith and is slidable in anendwise direction thereon. The cam 93 is disposed in a recess in the.under facepof the plate 87 of the auxiliary carriageof the camera A, sothat when the cam is rotated by the shaft 91, the plate 87' will beshifted lengthwise along the auxiliary carriage in one direction oranother the cam 93 will be shifted by the auxiliary carriage along theshaft 91. The shaft 91 is provided at its outer end with an operatinghandle 94 by means of which the shift ing ofthe camera may be effected.

A shaft 95 similar to 91 is rotatably mounted in a bearing 96 carried bythe main carriage 7, extends freely through the auxiliary carriage ofthe camera A, and slidably and rotatively through the carriage of thecamera B. An eccentric cam 97 (Figs. 2 and 3) is-keyed to and isslidable upon the shaft95 and engages in a recess in the under face ofthe plate 87 of the camera 13, so that when the shaft 95 is rotated byits handle 98 the camera B will be shifted to- Ward and from thesensitized plate and locked in position in a manner similar to thatdescribed for the camera A.

.A shaft 99 rot-atably mounted in a bearing 100 of the main carriage,extends freely through the auxiliary carriages of the cameras. A and Band has a slidable and rotatable bearing in the auxiliary carriage ofusages the camera 0. Aneccentric cam 101 is keyed to and is slidableupon the shaft 99 and engages in a recess in the under face of the plate87 of the camera C so that when the shaft 99 is rotated by its handle102, the eccentric cam 101 will shift the camera C toward and from thesensitized plate in a manner similar to that described for cam-- eras Aand B.

Ashaft 108 rotatably mounted in a hear: ing 104 in the main carriage 7extends freely through the auxiliary carri es for the cameras A, B and Oand has shdable and rotatable bearing in the auxiliary carriage of thecamera D. An eccentric cam 105 is keyed t0 and slidable upon the shaft108 and engages in a recess in the under face of the plate 87 of thecamera D so that when the shaft 103 is rotated by its operating handle106, the camera D will be shifted toward and from the sensitized plateand held in shifted positions in a manner similar to that described inconnection with cameras A, B and C. I

The main carriage isprovided upon its face towards the end frame 3 witha cylindrical t0ngue'107 (Fi 1) which is adapted to enter a recess in t-e end frame 3 when the main carriage has been shifted towards the endframe for contact printing. The tongue 107 may be locked within itsrecess by an eccentric cam (not shown) which is carried by the shaft 108of the end frame so as to project into the recess and rotated by ahandle 109. The main carriage may in this manner be locked againstdisplacement, the final movement of the negative boxes into contact withthe sensitized plates being effected by the handles 94, 98, 102 and 106.

The operation of the device for contact printing will now be described.The cameras A, B, C and D, arranged for contact printing, are mountedupon the plates 87 of the auxiliary carriages in the manner illustratedin Figures 2, 3, and 4 with the plates 87 at their. rearward limit ofmovement which can be effected by the operating handles 94, 98, 102 and106. The corresponding color negatives are mounted upon the ends of thenegative box in a manner well known in contact printing, withcorresponding edges of the negatives arranged parallel through theangalar adjustment of the negative boxes upon their supports. F

A number of sensitized printing plates 58 are stretched between thelower edges of the contact frames 45 and the stretcher plates 49, oneplate opposite each camera. The pressure beam 61 is shifted to theproper height for the first print by an operation of the handle 66. Thecameras are then shifted to one limit of movement transversely of theplatform :by an operation of the handle 77, or by an operation of themotor 80, or both. With the lever 38 operated to disconnect the splitnut sections 27 and 28 from the shaft 24, the main carriage may berolled along the platform 1 either by pulling the same or by anoperation of the operating handle 12. v

This movement may be completed at a slow rate if desired, by operatingthelever 38 to clutch the split nut sections 27 and 28 to the shaft 24.Then after the lever 17 has been operated to disconnect the pinion 10from the rack 9, an operation of the hand wheel 12 will causea rotationof the shaft 24 and cause a slow movement of the carriage along theplatform. In this manner the carriage may be shifted at a slow rate intoclose proximity to the end frame 3, with the tongue 107 entering therecess in the end frame, after which the handle 109 may be operated torotate the shaft 108 and carry its eccentric cam (not shown) intolocking engagement withthe tongue 107, which effectively locks the maincarriage to the end frame.

The levers 94, 98, 102 and 106 are then shifted-to carry the cameras A,B, C and D individually into tight contact with the sensitized plates.The sources of illumination within the lamp casings 88 are then renderedeffective for the period of time necessary to cause a roper exposure ofthe negative to the sensitized plate, after which the sources ofillumination are rendered ineffective- These exposures may bediagrammatically represented by the characters a, b, c and d in Figure8. Handles 94, 98, 102 and 106 are then operated in a reverse directionto move the cameras A, B, C and D individually away from the sensitizedplates, after which the hand wheel 77 is operated to shift all of theauxiliary carriages concomitantly and as a unit in a direction laterallyof the sensitized plates. During the lateral movement of the auxiliarycarriages as a unit, the micrometer dial 78, the pointer 79 and thecounter will indicate the extent of movement. After the auxiliarycarriages have been shifted until the negatives are brought op ositeunexposed portions of the sensitize la'tes, the movement is-stopped andthe hen les 94, 98, 102 and 106 operated to again shift the cameras A,B, C and D into contact with the sensitized plates. The sourcesofillumination in the cameras are then again rendered effective for theperiod necessary to photograph the' negatives again upon the sensitizedplates. These second exposures may be represented diagrammatically bythe letters a, b, c and d in Figure 8.

The handles 94, 98, 102 and 106 are then operated to shift the cameraout of contact with the sensitized plate and the auxiliary carriagesmoved again into new printing positions, after which hoto rap-hie printsa, b", c" and d are e ectee in the same manner. This method of printingis continued in a step by step manner until a number of prints have beenmade upon the sensitized plates. Then the plate carrying contact frame45 is shifted by an operation of the hand wheel 44 to bring a freshsection of the sensitized plates opposite the negative boxes of thecameras, after which new rows of photographic prints are made thereon ina manner similar to that described above for.

the first row.

During the spacing of the cameras for new exposures, it is unnecessaryto accurately measure the spacing between the print ing positionsbecause the prints from all.

register because they were correspondingly camera.

spaced. Thus, in Figure 8, if the squares 110 represent the prints ateach exposure, the shaded quarter sections thereof represent diaammatically the portion of the square w ich is to be rinted of thatparticular color, so that wlien a square 110 for each color is printedupon the same paper or article thecomponent colors will be accuratelysuperimposed as indicated diagrammatically in Figure 9.

When the picture or representation to be printed is small, and it isdesired to simultaneously print a large number of the same, considerabletime may be saved by-first pre paring multiple negatives, in a mannernow to be described. Upon the end frame 3 be tween the upper and loweredges of the contact frame, auxiliary negative holders 111 (Fig. 1) aresupported, one for each Each negatlve holder carries a photographicsensitized plate 112 with the sensitized surface facing the camera. Thecontact cameras which were used for contact printing are replaced bycameras A, B, C

and D (A' onlybeing shown) which are used for projection printing. Thedetails of these cameras are well known and a detailed description isunnecessary. It may be said, however, that the master color negativesare mounted in the projection cameras in a manner known in the art, andwhen the sources of light in the lamp casing are made effective, imagesof the color negatives will be projected upon the sensitized platescarried 1n the negative holders.

With this arrangement the master color negatives are projected upon thesensitized plates 112 in a step and repeat order, the

' cameras being shifted laterally by operation of the hand wheel 77 orby the motor, as described before in connection with contact printing;The images projected upon the respondingly spaced in the different colorI printing plates so that when one printis al gned for each color plate,the other prints of the same plate are automatically aligned.

It will be understood that either the master or auxiliary colornegatives may be protographed upon the sensitized metal plates byprojection printing in the same order of concomitant lateral movementsas described for contact printing, in order to obtain color .pr'ntingplates with correspondingly spaced multiple prints thereon, at the same,enlarged or reduced sizes relatively to the color negatives projected.

Throughout the specification and claims, wherever I have referred tosensitized plates, I mean any plate,

it is to be understood that film, or similar object having a sensitizedphotographic coating thereon, upon which photographs'may be made. WhileI have illustrated and described apparatus for" printing four colors, itis to be understood that the number of colors printed may be increasedor decreased as desired. The apparatus herein described and illustratedis similar in parts to that disclosed in my copending application filed.April 26, 1919, Serial No. 292,980.

It will be understood that various changcs in. the'details andarrangement of parts herein described and illustrated for thepurpose ofexplaining thelnature. of the invention may be made by those skilled-inthe art within the principle and scope of the invention. I Q

I claim:

1. The method of producing multiple photographic plates for color,register work, which comprises providing a color negative and asensitized plate for each color to be printed, producing steppedrelative'movement between the negatives as a group and the plates as agroup, and photographing the negatives upon the sensitized plates ateach step to provide a plurality of correspondingly spaced photographsupon each p ate.

2. The method of producing multiple printing plates for color registerwork, which comprises producing a mastercolor negative for each colorto-be printed, producing simultaneous and equal-increments of. movementbetween the master color negatives as a unit and a plurality ofsensitized plates as a unit, one late for each master negative,photographing the master color negatives upon their corresponding.plates at the ends of the incrementsof movements, for roducing upon eachplate when develope a plurality of pictures vof its master color neative corresponding in spac'ng to the spacing of the pictures upon theother plates, of their color negative, and then forming printing platesfrom the multiple picture plates as negatives."

3. The method of producing multiple printing platesv for color registerwork, which comprises producing a master color negative for each colorto be printed, producing simultaneous and equal increments of movementbetween the master color negatives as a unit and a plurality ofsensitized plates as a unit, one' late for each master negative,photographmg' the master color .negatives upon' their: correspondingplates at the ends of the increments'of movements, for producing uponeach plate when developed a plurality of pictures of its master colornegative, corresponding in spacing to the spacing otthepictures' uponthe other plates'of their color negative, then using the multiplepicture plates as' new color negatives and producingsimultaneous andequal increments of movements between the new color negatives as a-unitand a plurality of sensitized printing plates as a unit, one printingplate for each newcolor negative, photographing the new color negativesupon their corresponding sensitized printing plates at the ends of theincrement of movement, for producin upon each printing plate whendeveloped a plurality of pietures of its new color negativecorresponding exactly in spacing to the spacing of the pictures upon theother printing plates for the other colors.

4. The method of producing multiple photographic plates for colorregister work, which comprises producing simultaneous and equalmovements between the. color negatives and the sensitized plates fromone photographic position to another, and photographing the negativesupon the plates at each position to provide a plurality of photographsupon each plate which correspond exactly in spacing with those of eachof the other plates.

5. Apparatus for the production of multiple photographic plates .forcolor register work, which comprises means for supporting a plurality ofsensitized plates, means for supporting a plurality of color negativesin positions for printing one on each of the lates, means for causingsimultaneous an equal relative increments of movements between said twosupporting means to place each negative in a new photographic positionrelative to its plate at the end of each increment of relative movement,whereby a printing exposure at each photographic position will result inthe formation on each developed plate of a plurality of picturesof thenegative which are spaced correspondingly with thepictures on u tives inpositions for printing one on each of the plates, means for impartingincrements of movement to the negative supporting means as a unit in adirection transverse to a normal to the surfaces of the sensitizedplates, whereby a printing exposure at the end of each increment ofmovement will result in the formation 'oneach developed plate of aplurality of pictures of the negative which are spaced correspondinglywith the pictures of all the other color plates. i

7. Apparatus for the production of multiple photographic plates forcolor register work, comprising a support, means for mounting aplurality of sensitized plates in parallel planes on said support, asecond support movable transversely to a normal to the surface of one ofthe plates, a lurality of diflerent color negatives carri by said secondsupport and spaced thereon for printing co-operation, one with each.plate, and means for shifting the second support with its negatives as aunit through increments of movement into a succession of printingpositions.

8. Apparatus for the production of multiple photographic plates forcolor register work, comprising a support, means for mounting aplurality of sensitized plates in parallel planes on said support, asecond support movable transversely to a normal to the surface of one ofthe plates, a lurality of different color negatives carri by said secondsupport and spaced thereon for printing co-operation, one with eachplate, means for shifting the second support with its negatives as aunit through increments of movement into a succession of printingpositions, and means for photographically exposing each negative to itscorresponding plate in each printing position whereby each of the plateswhen developed will bear a series of pictures of a color negative whichare spaced correspondingly to the pictures.

on the. other plates formed from the other color negatives.

In witness whereof I hereunto subscribe my signature.

HERMAN C. BOEDICKER.

